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NEWTON’S LAWS via ART – PART II


Abraham Tamir

 

Newton’s Second Law: law of acceleration

Newton's First Law deals with an object with no net force. Newton's Second Law talks about an object that has net force acting on it.  Firstly, the law states that if you do place a force on an object, it will accelerate, i.e., change its velocity, and it will change its velocity in the direction of the force.  Secondly, this acceleration is directly proportional to the force.  For example, if you are pushing on an object, causing it to accelerate, and then you push, say, three times harder, the acceleration will be three times greater.  Thirdly, this acceleration is inversely proportional to the mass of the object. For example, if you are pushing equally on two objects, and one of the objects has five times more mass than the other, it will accelerate at one fifth the acceleration of the other.  The Second Law formulated at about 1792 gives us an exact relationship between the net force F acting on a body, its mass m, and the acceleration a of the body due to the force. It can be expressed as a mathematical equation by FORCE = MASS times ACCELERATION, namely

                                  F = ma

The equation is very aesthetic since all the powers in it are exactly 1.  The following are the definitions of the quantities in the above formula that are demonstrated below by different artworks.  The force F is anything that can cause a massive body to accelerate.  It may be experienced as a lift, a push, or a pull.  Force was first mentioned by Archimedes in the 3rd century BC but only mathematically defined by Isaac Newton in the 17th century.   Force was first mentioned by Archimedes in the 3rd century BC but only mathematically defined by Isaac Newton in the 17th century.

 

 

Fig.15: Demonstrations of the Force F

 

Figs. 15 and 16 are artistic demonstrations of force F where Rene Magritte painted the picture on the left-hand-side of Fig.15; the other pictures are by unknown artists.

 

Fig.16: Demonstrations of Force F

 

Mass is a fundamental concept, roughly corresponding to the intuitive idea of "how much matter there is in an object".  Mass m is usually defined as the quantity of matter in a body, its inertia, or resistance to acceleration.  Fig.17 are different artistic demonstrations of mass.  On top-left is a sculpture photographed by the author in Coruna – Spain where top-right was photographed in a gallery in Paris.  Bottom-left was painted by the Austrian De

 

 

Fig.17: Demonstrations of Mass m

 

Es Schwertberger (b.1942), a myth and mystery artist.  On bottom-right is an artwork by Fernando Botero.  Fig. 18 demonstrates masses approaches infinity (Left) and masses approaching zero (Right).  On the left-top is a sculpture by Fernando Botero where on right-top is a sculpture by Alberto Giacometti (1901-1966), a Swiss surrealist painter and sculptor.  The author photographed the picture in the bottom.

 

 

Fig.17: Mass approaching infinity (Left) and Mass approaching zero (Right)

                       

Finally the concept of acceleration a is demonstrated via art by falling bodies.  a is defined by the rate at which an object's velocity changes with time.  On the left-hand-side is an artwork of falling drops by Anatoli Fomenko  (b.1945), a Ukraine scientist-art & mathematics.

 

Fig.18. Demonstration of acceleration

 

Fig.19 demonstrates Newton’s Second Law by a single artwork.  The artwork on the left was painted by Franz Stuck (1863 -1928), a German Symbolist/Art Nouveau painter, sculptor, engraver, and architect.   The artwork in the middle is a sculpture constructed by Rafi Carasso (b.1945), an Israeli medical doctor and artist.  Fernando Botero painted the image on the right.

 

 

 


 

Fig.19. Newton’s Second Law F = mg

 

 

      Newton’s Third Law: Action = Reaction

Newton's Third Law of motion states: ”all forces in the universe occur in equal but oppositely directed pairs”.  There are no isolated forces; for every external force that acts on an object there is a force of equal magnitude but opposite direction that acts back on the object, which exerted that external force.  In other words “when one body exerts a force on the other, then the second body exerts a force equal in magnitude and opposite in direction on the first body, namely, action = reaction.”  Thus, in the interaction between a system and its surroundings, forces always appear in pairs where each force acts on the other body.  This is also the reason why they do not cancel each other.

    We usually do not pay attention to the fact that this law is active at “every corner”, and that every time we interact with our surroundings we feel the law.  The following are a few examples.  When you punch someone in the face, your hand not only applies a force to the person's face; the person's face applies a force to your hand.   Since the person's face is softer than your hand it suffers more from the interaction.  When we press our lips one against the other we feel some pain in both lips because of the force that is exerted.  When we stand on the floor we feel our weight (the action) only due to reaction of the floor on our legs.  Sprinters usually apply some force with their legs on some slanted objects.  The reaction force of the object, according to Newton’s Second Law, provides an initial acceleration to the sprinter, which is proportional to his mass.  As far as it looks surprising, a falling body attracts earth upwards at the same force as earth attracts the body downwards.   However, since earth acceleration upwards is much smaller than acceleration g it is impossible to see any motion of earth.  The Third Law is very important for space travel.  In the cold void of space there is no air for jets to suck or for propellers to churn, and yet space ships can maneuver in a vacuum.  How do they do it? The engines propel gas particles out the back of the space ship. Since every force has an equal and opposite reaction force, the space ship will be propelled forwards. Because of the First Law, space ships do not need very much fuel - once they are moving they will stay in motion because friction, the opposing force, is negligible.  A bird flies by use of its wings. The wings of a bird push air downwards. In turn, the air reacts by pushing the bird upwards.  The size of the force on the air equals the size of the force on the bird; the direction of the force on the air (downwards) is opposite to the direction of the force on the bird (upwards). An automobile is equipped with wheels that rotate backwards. As the wheels rotate backwards, they push the road backwards.  In turn, the road reacts by pushing the wheels forward. The size of the force on the road equals the size of the force on the wheels; the direction of the force on the road (backwards) is opposite to the direction of the force on the wheels (forwards).  Thus action-reaction force pairs make it possible for automobiles to move as well as birds to fly. 

In the following, Newton’s Third Law is demonstrated by different artworks that describe different applications of the law.  Fig.20 is a sculpture constructed by Dudu Geva (1950-2005), Israeli caricaturist.  The sculpture is of David Ben-Gurion (1886-1973), Zionist leader, founder of the state of Israel and Israel's first and longest-serving Prime Minister.  The original sculpture is on the left-hand-side, however both cases demonstrate different possibilities of the third law.  Fig.20 is an artwork of Fernando Botero.  In addition to the marked places where the law is active, it takes place also between the leaning head of the woman and her palm or between the fingers of the woman and the plate she is holding.  Figs.22, 23 are additional demonstrations of the Law.  Fig.23 left is a caricature of the Israeli Minister Fuad Ben Eliezer painted by the Israeli caricaturist Moshik Lynn (b.1950).  Note that when Fuad is closing his mouth, identical forces in opposite directions are created between the two lips.  Fig.24 demonstrates the idea that Newton’s Laws are applicable not only on earth but also on other galaxies.  On the picture of Callisto, the moon of the planet Jupiter, the author “transplanted” on each of the above stars the dancing couple of Botero that demonstrates Newton’s Third Law.  The only difference between the two stars is that on Jupiter, the action created by the weights of the bodies will be higher by a factor of two because the acceleration gravity on it, 2.45 m/s2, is higher by a factor of two than on Callisto.

 

 

 

Fig.20. Newton’s Third Law: Action = Reaction

 

 

 

 

Fig.21. Newton’s Third Law

 

 

 

 

 

 

 

Fig.22. Newton’s Third Law

 

 

 

Fig.23. Newton’s Third Law

 

 

 

Fig.24. Newton’s Third Law is applicable everywhere in the universe

 

 

Fig.25. What happens without reaction?

 

Fig.25 demonstrates what may happen if reaction would not have existed when reaction

 

takes place.  So what happens is that the cup of coffee will penetrate into the brain as seen by the X-ray view created by the author.  Terrible!!!  So we may thank God that created order in our universe, for example action = reaction as well as the other laws.

            As in Newton’s First Law, the following cases demonstrate qualitatively Newton’s Third Law.  For example Fig.26 of the British fantasy art painter Brian Froud (b.1947) demonstrates the following saying in psychology: “Don’t push too hard (action) because there will be a reaction”.

 

 

Fig.26: Newton’s Third Law demonstrated qualitatively

 

Fig.27 is another example demonstrating action = reaction that was painted by the American Alex Grey (b.1953), an anatomy of the body artist.

 

 

Fig.27: Newton’s Third Law:

Action: He loves her.  Reaction: She loves him

Fig.28 is the final example demonstrating qualitatively Newton’s Third Law according to which: Action: Invest in education.  Reaction: You will raise Einsteins.

 

 

 

Fig.28: Newton’s Third Law

 

Newton’s Universal Law of Gravity

The major assumption in Newton’s universe was that the mass m of a body is the major factor in the formation of the “Gravity Force” F where in the absence of mass there is no gravity.

 

 

Fig.29. The Solar System

According to “Newton’s General Law of Gravitation” the force F between two masses is  defined by

 

                                          F = m1m2/r2

 

where m1 and m2 are the masses of the two bodies and r is the distance between them. The equilibrium between the above force and m(v2/r) - the centrifugal force, keeps all bodies in a stable circular motion.  Fig.29, painted by the American Ron Miller (b.1947), an artist and author of astronomical books, demonstrates the Solar System and gives the impression of the above stable equilibrium.

 In conclusion it is expected that the above demonstrations by art of Newton’s laws make them more understandable, perceptible and easy to remember.